It was hard to picture how “The Sessions” (2012) would ever navigate its subject, real-life polio victim Mark O’Brien’s quest to lose his virginity, iron lung be damned. Yes, the late O’Brien, a Berkeley journalist and poet, had written about his experience going to a sex therapist, so there was something of a template. (He was also profiled in the 1996 documentary “Breathing Lessons.”) But what tone to expect from a dramatization? Cloying? Intolerably depressing? Even, dare it be said, a bit of the same gaping that “L.A. Law” did at the whole sex-surrogacy concept way back when? None of the above. John Hawkes, Oscar nominee Helen Hunt, and writer-director Ben Lewin deliver a dramatically measured and wryly humorous film that’s moving without being draining. Hawkes, a chameleonic wonder in the otherwise overrated “Winter’s Bone,” similarly disappears into his role here, a mix of anxiety and anticipation, of matter-of-fact strength and suppresseddespair. Hunt, as Salem native Cheryl Cohen Greene, does brave work (you wonder what sort of career spike Hunt might see) and intriguingly bookends her performance as a paraplegic’s lover in 1992’s “The Waterdance.” William H. Macy is key to the lighter moments as a hipster priest advising O’Brien; Moon Bloodgood (“Faster”) is a surprise as O’Brien’s acerbically witty caretaker. Extras: Cast interviews; on Blu-ray, a segment with Lewin, 66, himself a polio survivor. (Fox, $22.98; Blu-ray, $29.99)

ACTION